In wet shaving systems, factors such as the frictional drag of the razor across the skin, the force needed to sever hairs, and irritation of pre-existing skin damage can create a degree of shaving discomfort. Discomfort, and other problems accompanying wet shaving systems, can be alleviated by the application of shaving aids to the skin. Shaving aids may be applied prior to, during, or after shaving. A number of problems accompany the use of pre- and post-applied shaving aids. Pre-applied-shaving aids can evaporate or can be carried away from the site of application by repeated strokes of the razor. Post-applied-shaving aids are not present on the skin during shaving and thus their application may be too late to prevent an unwanted affect. Both pre-applied and post-applied shaving aids add additional steps to the shaving process.
Shaving aids, e.g., a lubricant, whisker softener, razor cleanser, medicinal agent, cosmetic agent or combination thereof, have been incorporated into razors, for example by incorporating a shaving aid into one or more molded polymeric components of the razor. U.S. Pat. No. 5,113,585 to Rogers discloses a shaving aid composite that includes a water-soluble shaving aid, e.g. polyethylene oxide, dispersed within a water insoluble matrix material, e.g., a polystyrene polymer. Such shaving aid composites have been mounted on razor cartridge structure. Upon exposure to water, the water-soluble shaving aid leaches from the composite onto the skin and the composite tends to swell.
U.S. Pat. No. 6,442,839 mentions mineral oil as one of a number of shaving aids that may be included in the water insoluble matrix. Mineral oil has also been used as a plasticizer for the water insoluble material in shaving aid composites used on various commercially available razors. In these instances, the mineral oil is bound to the water insoluble material and does not leach out of the shaving aid composite during shaving. Mineral oil is mentioned in U.S. Pat. No. 6,182,365 as a plasticizer present in a particular thermoplastic elastomer that may be used in a skin engaging member for a razor.
Commercial products have been sold by The Gillette Company, more than one year prior to the filing date of the present application, in which the shaving aid composite included polyethylene oxide that had been spray coated with Vitamin E and botanical oils such as grapeseed and avocado oils.